Power Quality (PQ) indices are a powerful tool for quickly quantifying PQ disturbances. They also serve as the basis for illustrating the negative impact of electrical disturbances on components and for assessing compliance with the required standards and recommendations within a regulating framework. Within these pages lies a comprehensive overview of both the traditional PQ indices in use today and new indices likely to be used in the future. Key features of this book include: a special focus on the metrics for quantifying PQ disturbances; a complete review of methods and indices for assessing disturbance responsibilities between customers and utilities; a survey on PQ objectives around the world, with highlights on the economic aspects of PQ disturbances. Inside, you will find a thorough and well-balanced treatment on theoretical concepts and practical applications, enhanced by examples and exercises of PQ indices computation and use. This is an important resource for academics, students of power quality, reliability and electrical power systems courses, and also for practicing engineers involved in solving PQ problems in the new structures of liberalised energy markets.